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bdurbrow

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  1. Could you design in the extra hardware to operate bidirectionally, and just not populate that area of the PCB for the unidirectional boards?
  2. I don't recall any diagnostic software ever outputting over SCSI... but that doesn't necessarily mean that there never was any. As for which software to use, it depends on which Mac you are having trouble with.
  3. Or, if you do, you are also implicitly specifying the resistance of the circuit. R=V/I - "Ya canna' violate the laws of physics, cap'n!" Lt. Cmdr Montgomery Scott. I think it depends on who "you" is, and how unlucky you are. Sometimes people have heart conditions that they don't know about. On the other hand, I just got back from traveling at a closing speed of over 120 miles per hour in close proximity to other vehicles being operated by a bunch of yahoos... any error during the course of which could well have been fatal (and indeed, something in the neighborhood of thirty-two th
  4. FWIW, it's a common myth (er, oversimplification, really) that electricity takes the path of least resistance - it actually takes ALL paths, but how much flows thru any given path depends on the resistance of that path as compared to the rest of the paths. If, for example, you have a positive source connected to your right thumb, and a negative source connected to your right pinky finger, there will be some flow thru your heart - but it will be vastly smaller than the flow from your finger to your thumb, because the resistance of the path that goes thru your heart is so much greater. Usual
  5. Also known as "spudgers" - and no, I have no idea where the name came from. But - yeah, they're great to have around; especially for those doggon' FFC connectors.
  6. Both my 128k and SE won't open just by gentle shaking... but, they are early machines, so perhaps the molds they were made from were a bit tighter than yours? IIRC, the Aquadag on the inside of the CRT is pulled to positive 15 to 30 kv or so relative to ground (which is why that terminal is called the anode - it's positive), by a high voltage transformer and diode arrangement. Usually this high voltage circuit is completely enclosed in a high-voltage insulator, and there isn't any high voltage on the driver PCB itself, but I'm not familiar with the specifics of the SE's high voltage drive
  7. Umm... that's a Torx T15, not a T8. Also, a sheet metal spring clamp to pry the case open after removing the screws is handy. Ditto on the not-electrocuting yourself part. Compact Macs have CRTs in them that retain high voltage even when turned off and unplugged... and there's enough capacity in the CRT to cause your heart to stop if you get the current flow thru your body just wrong - and if you do happen to survive, I'm told that it really, really hurts. So, make sure you discharge the CRT before digging around inside it. If you are not comfortable doing this; then it's best to
  8. You are in a maze of twisty little wires, all alike. >
  9. Well, I'm no expert on ][ drives, but... That looks like an inductor; and if I'm right, then there's nothing inside it to be leaking out. I agree with Joe - it's most likely glue; commonly called "Silastic" (even though that's a trademark; see https://en.wikipedia.org/wiki/Silastic --- kinda like asking for a Kleenex or a Xerox, even though you're going to be handed a generic facial tissue and a photocopy made on a machine manufactured by Cannon or HP). It might help if you could be more specific about what, exactly, it's doing? And are the symptoms specific to that particular drive
  10. Oh, and it's still got some charge on it: a whole whopping 50 millivolts!
  11. So, I just popped open that SE that I was given, fearing the worst... but, NO! No acid spilled across the Logic Board: ... and that battery has a date code of 6/88!
  12. There are FPGAs that can do DVI and HDMI directly; and I have here an FPGA dev board (Papillo with an Arcade MegaWing) that does VGA via a R2R ladder.
  13. FWIW, I have a 128K Mac that's been upgraded with a Levco Monster Mac card, and the Mac Plus ROMs... that wouldn't boot. At first I thought it was the EPROMs on the Monster Mac card that had died (they were found to be missing the UV shielding cover that keeps them from being slowly erased), but it turned out to be the mask ROMs on the main Logic Board.
  14. It's probably making a bunch of Color QuickDraw calls; even if the display is in single-bit-per-pixel mode.
  15. The video on a compact Mac is TTL, and not at a standard frame rate. For streaming, you would probably be better off running the games in an emulator and streaming that out via a video capture app on your modern Mac/PC. In principal one could create some new hardware to capture the TTL video and input it via USB (perhaps with a fast ARM micro controller that had a high-speed USB 2 port on it), but it would be a non-trivial project.
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